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We adopted green synthesis of multifunctional Cerium oxide nanoparticles (CeO2 NPs) by low temperature solution combustion route employing Aloe vera (L.) Burm f. leaf gel as a fuel. The synthesized CeO2 NPs were characterized by PXRD, SEM, and TEM. Results showed that size of NPs between 40 and 50 nm and they found highly crystalline. These NPs were tested in vitro for their antimicrobial activity against four bacteria (Staphylococcus aureus, Enterobacter aerogenes, Pseudomonas aeruginosa and Escherichia coli) and three fungi (Aspergillus niger, A. clavatus and A. flavus). Results showed toxicity against both the tested bacteria and fungi. Maximum zone of inhibition from bacteria and fungi was obtained from 75 µg/ml CeO2 NPs against E. aerogenes (21.67 ± 1.21) and A. flavus (19.00 ± 1.73) respectively. Current investigation explores the green facile method for synthesis of multifunctional rare earth CeO2 NPs with interesting structural and surface morphological and biological studies. [ABSTRACT FROM AUTHOR]

For the first time green route method was used to synthesize pure and Mg2+ (1-11 mol%) doped Y2O3 nanophosphors by using Aloe vera leaves extract as a fuel. The final product was well characterized by powder X-ray diffraction (PXRD) and transmission electron microscopy (TEM). The PXRD results showed formation of single phase, cubic structure of Y2O3 with crystallite sizes ~ 25 nm and TEM images showed crystallite size of the material and were found to be around ~ 25 nm. In an in vitro test, nanocomposites showed significant antibacterial activity against four different gram negative human pathogenic microorganisms viz., Salmonella typhimurium, Enterobacter aerogenes, Pseudomonas aeruginosa and Escherichia coli and maximum zone of inhibition is observed from Y2O3/Mg (1%) nanocomposites which is closely comparable with the standard commercial drug streptomycin. Whereas, the nanoparticles and nanocomposites have showed significant DPPH and H2O2 scavenging activity, higher scavenging activity were registered in Y2O3/Mg (1%) and Y2O3/Mg (5%) respectively. [ABSTRACT FROM AUTHOR]

This paper reports an improvement in Pt/n-GaN metal-semiconductor (MS) Schottky diode characteristics by the introduction of a layer of HfO2 (5 nm) between the metal and semiconductor interface. The resulting Pt/HfO2/n-GaN metal-insulator- semiconductor (MIS) Schottky diode showed an increase in rectification ratio from 35.9 to 98.9(@ 2V), increase in barrier height (0.52 eV to 0.63eV) and a reduction in ideality factor (2.1 to 1.3) as compared to the MS Schottky. Epitaxial n-type GaN films of thickness 300nm were grown using plasma assisted molecular beam epitaxy (PAMBE). The crystalline and optical qualities of the films were confirmed using high resolution X-ray diffraction and photoluminescence measurements. Metal-semiconductor (Pt/n-GaN) and metal-insulator-semiconductor (Pt/HfO2/n-GaN) Schottky diodes were fabricated. To gain further understanding of the Pt/HfO2/GaN interface, I-V characterisation was carried out on the MIS Schottky diode over a temperature range of 150 K to 370 K. The barrier height was found to increase (0.3 eV to 0.79 eV) and the ideality factor decreased (3.6 to 1.2) with increase in temperature from 150 K to 370 K. This temperature dependence was attributed to the inhomogeneous nature of the contact and the explanation was validated by fitting the experimental data into a Gaussian distribution of barrier heights. [ABSTRACT FROM AUTHOR]

Precocious puberty still remains an elusive diagnosis in the majority of patients. Infrequently, lesions of the central nervous system are associated with sexual precocity. Depending on their location, these cysts may affect many systems, however, there is little information concerning their involvement in endocrinological disorders. We report a case of a sylvian cistern arachnoid cyst presenting with precocious puberty in a 3-year-old girl. The child recovered following a cystoperitoneal shunt. The mass effect of the arachnoid cyst upon the hypothalamus was, at least in part, responsible for the development of precocious puberty. To the best of our knowledge, this is the 1st case of a sylvian cistern arachnoid cyst presenting with precocious puberty. The role of surgical decompression of the cyst is also discussed. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

INTRODUCTION Epidermoids of the lateral ventricle are relatively rare tumours. As these tumours are soft and relatively avascular, they appear to be ideally suited for endoscopic surgical excision. At present the instruments available are specifically designed for endoscopic intra ventricular surgeries, limitations being inability to rapidly debulk the tumour and achieve adequate haemostasis. We present a case of lateral ventricular epidermoid that was excised endoscopically using a system originally designed for endoscopic disc surgery. PRESENTATION OF CASE We describe a female patient who presented with recurrent headache and occasional episodes of vomiting since 6 years. Preoperative diagnosis of lateral intra ventricular epidermoid was made with the help of an Magnetic resonance imaging (MRI) of the brain. Intraoperatively, an incision was made over the right Kocher's point and a 2.5 cm dural opening was made following a small craniotomy and the Destaudeau endoscope was introduced. A 30° scope and gentle manipulation were used to view the ventricular cavity and ensure near total excision of the tumour. Here we record this novel technique. DISCUSSION Lateral intra-ventricular tumours are usually approached through a trans-cortical or intra hemispheric approach, under microscope. The use of endoscopes have been largely restricted because of non-availability and relative difficulty in controlling troublesome bleeding, incase of vascular tumours. CONCLUSION A multi portal endoscope that allows use of routine pituitary instruments would enable the surgeon to achieve haemostasis effectively and, in our opinion, should be a viable alternative to microscope for excision of intra ventricular tumours. [ABSTRACT FROM AUTHOR]

Adenoid cystic carcinoma (ACC) is a rare malignant tumour of the major salivary glands. It accounts for 10-15% of all salivary gland tumours and 1% of all head and neck tumours. Surgical resection followed by radiation is the choice of treatment for ACC. However, late loco-regional recurrence and metastasis is often seen emphasizing the importance of long-term follow-up. We report an unusual case of extradural metastasis of ACC in the dorsal spine. The primary submandibular gland tumour was resected 11 y back. A recurrence had been detected two years prior to the occurrence of spinal metastasis. Surgical decompression was done which was followed by palliative radiotherapy. Patient is symptomatically better, ambulant and on regular follow-up. [ABSTRACT FROM AUTHOR]

Fast and accurate detection of light in the near-infrared (NIR) spectral range plays a crucial role in modern society, from alleviating speed and capacity bottlenecks in optical communications to enhancing the control and safety of autonomous vehicles through NIR imaging systems. Several technological platforms are currently under investigation to improve NIR photodetection, aiming to surpass the performance of established III-V semiconductor p-i-n (PIN) junction technology. These platforms include in situ -grown inorganic nanocrystals (NCs) and nanowire arrays, as well as hybrid organic-inorganic materials such as graphene-perovskite heterostructures. However, challenges remain in NC and nanowire growth, large-area fabrication of high-quality 2D materials, and the fabrication of devices for practical applications. Here, we explore the potential for tailored semiconductor NCs to enhance the responsivity of planar metal-semiconductor-metal (MSM) photodetectors. MSM technology offers ease of fabrication and fast response times compared to PIN detectors. We observe enhancement of the optical-to-electric conversion efficiency by up to a factor of ∼2.5 through the application of plasmonically-active semiconductor nanorods and NCs. We present a protocol for synthesizing and rapidly testing the performance of non-stoichiometric tungsten oxide (WO3-x) nanorods and cesium-doped tungsten oxide (Cs y WO3-x) hexagonal nanoprisms prepared in colloidal suspensions and drop-cast onto photodetector surfaces. The results demonstrate the potential for a cost-effective and scalable method exploiting tailored NCs to improve the performance of NIR optoelectronic devices., (Creative Commons Attribution license.)